Jubilant: County celebrate Alex Schalk’s second goal for the club which gave them clear daylight in the second half (Picture from BBC Scotland)

ROSS County reached their first ever Scottish League Cup final as 10-man Celtic’s domestic treble hopes were dashed for a second successive season at a rain-soaked Hampden Park.

Gary Mackay-Steven looked to have set the holders on the way inside 27 seconds by stroking into an empty net but Martin Woods replied from the spot after Efe Ambrose saw red on 13 minutes for bringing down Alex Schalk as the last man.

Paul Quinn headed home early in the second half on his second County debut before Schalk fired home an unstoppable shot from the edge of the box to make it 3-1.

Leigh Griffiths saw a fiercely-struck penalty and another deflected low effort kept out superbly by Staggies keeper Scott Fox during a tense finale.

The Premiership leaders were in sparkling form heading into Ronny Deila’s 100th game in charge but – after another catastrophic semi-final loss – must now focus on sealing a fifth successive league title and progressing in the Scottish Cup.

The post-mortem continued in the Hampden dressing room for over half-an-hour after the final whistle – and the Hoops will need a quick response with a trip to second-placed Aberdeen on Wednesday night.

Scoring groove: Mackay-Steven’s three goals this term have now come in two games after his St Johnstone brace (Picture from BBC Scotland)

The Staggies – fourth in the Premiership – must have feared the worst when the Hoops made the best possible start as Griffiths raced on to Calum McGregor’s poked pass and squared unselfishly for Mackay-Steven to sweep home straight from the kick-off.

Celtic, bidding to reach their 31st League Cup final, could have been out of sight in the opening exchanges had Ambrose managed to convert two set-piece opportunities.

The centre-back’s first header was scrambled off the goalline by Richard Foster before he steered another Stuart Armstrong corner off target when well placed from six yards.

But the tie turned dramatically when the Nigerian international was ordered off by referee Craig Thomson for cutting across the knee of Schalk – who would have been clean through from Jackson Irvine’s pass which was flicked on by Woods.

Foul: Ambrose made slight contact with Schalk’s knee which knocked the Dutch U21 forward off balance (Picture from BBC Scotland)Red card: Ambrose was also dismissed in a goalless draw against Hearts in September (Picture from BBC Scotland)

The County midfielder had to wait for McGregor to be sacrificed, for Danish defender Erik Sviatchenko to make his debut, before sending Craig Gordon the wrong way from the spot for his first goal of the season.

Celtic slowly reasserted their superiority as Armstrong curled narrowly over from 18 yards after County appealed in vain for an offside flag.

Seeking to cash in on their numerical advantage, the Staggies made a tactical change with Jonathan Franks replacing Stewart Murdoch just before the half-hour mark.

It came as County gained a foothold with Gordon parrying behind a fizzing 25-yard effort from man of the match Woods but Celtic ended the first half strongly as stand-in skipper Mikael Lustig’s header was repelled by a stretching Fox.

McIntyre’s team, however, completed a stunning turnaround just three minutes into the second half from a set-piece routine executed to absolute perfection.

Woods’ curling corner was nodded back across by captain Andrew Davies for fellow centre-back Quinn to nod home from close range.

Impact: Quinn scored Aberdeen’s winner in their 2-1 victory over Celtic in September and made his second Staggies debut after re-joining from Pittodrie (Picture from BBC Scotland)

Amid the driving Glasgow rain, Celtic’s 10 men offered a meek response and found themselves further adrift just after the hour mark.

Woods was again heavily involved with a driving run and incisive pass for Dutchman Schalk, who took one touch to control before rifling into the roof of the net to spark wild celebrations in the County end.

It prompted some Celtic fans to head for an early exit but – despite the introduction of captain Scott Brown after two months out injured – a stirring comeback was not forthcoming.

Return: The Celtic skipper made his first appearance since picking up a knee injury against Kilmarnock on November 21 (Picture from BBC Scotland)

The Hoops had a golden opportunity to reduce the arrears yet Griffiths could not add to his 27 goals this season as Fox pulled off a crucial save from the spot after County substitute Brian Graham was harshly adjudged to have handled in the box.

Fox also had to react well to shovel another Griffiths effort over the crossbar, which had taken a slight deflection off the boot of Davies.

At the other end, Irvine almost made it more convincing for County when his well-struck volley was beaten away by Gordon from Michael Gardyne’s cross.

The Staggies defended their two-goal cushion resolutely to close out a famous win in their first-ever League Cup semi-final.

For 15-time winners Celtic, it was another sobering experience at the national stadium where their defensive vulnerability was magnified – and Deila’s future will again be on the agenda as the latest dream of a third clean sweep in their history was popped.

Change in fortune: County have lost both league encounters with Premiership champions Celtic this season (Picture from BBC Scotland)

“It’s a fantastic achievement for the club and I am really pleased for the chairman as he has done so much for the club down the years. We were determined to give him a second trip to a national final. We thought the way it started it was going to be a long afternoon for us.

“We set up to be stiff and that was anything but stiff. We had to hang in and it was a matter of bottle. We had a bit of luck and getting the penalty got us back into it. But Celtic are a great team and Scott Fox made some incredible saves. It should be a great day in the final.”

Missed chance: The Norwegian was seeking to retain the League Cup in his second season in charge (Picture from BBC Scotland)

“We had everything in our hands but the red card changed everything. 80 minutes with 10 men makes it hard for us. I haven’t talked to Efe about it [the red card] but he’s very disappointed. That’s how football is.

“In the end it’s my responsibility and I’m very disappointed today. All the players are too but what’s done is done. In three days we go into a very important game and we have to look forward to that.”

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